P2 Questions

• What does a a material's thermal conductivity tell you?


  How well it conducts heat
• Which materials have a low thermal conductivity?


  Thermal Insulators
• Give three factors that determine the rate of thermal energy transfer through a material.


  Thermal conductivity, temperature difference, thickness.
• What factors affect the rate of heat loss from a building?

  Thermal conductivity of walls and roof, Thickness or walls and roof, Temperature difference between the two sides of the wall/roof.
• Specific heat capacity


  Amount of energy need a to raise the temperature of 1kg of material by 1 degree.
• 5 types of insulation

  • double glazed windows
  • loft insulation
  • draft excluders
  • floor insulation
  • cavity wall insulation
• Give 2 advantages on solar panels

  • good for the environment
  • minimal maintenance required
• Give two disadvantages on solar panels

  • Expensive
  • Weather is unreliable
• Cavity wall insulation

  Cavity wall insulation reduces the rate of energy transfer through the outer walls of the house. The cavity of an outer wall is the space between the two layers of brick that make up the wall. The insulation is pumped into the cavity. It is a better insulator than the air it replaces. It traps the air in small pockets reducing the rate of energy transfer by conduction.
• Specific Heat capacity equation